The man who stabbed broadcaster Barry Soper's son has been sentenced to four months home detention, and 200 hours of community work.

Jon Gary Edwards, 38, had earlier pleaded guilty to wounding with intent to injure, after he stabbed then-23-year-old Henry Soper on a night out in Wellington.

Soper had been out with friends on the night of the attack in July last year, having recently returned to Wellington from Melbourne.

According to the agreed summary of facts, Soper had been playing a slot machine, when Edwards approached him and they had a short verbal argument about the use of the slot machine.

Edwards then went outside to wait for Soper. When Soper went to the reception area later to collect some winnings, Edwards approached him and asked him to come outside.

When Soper told him to leave, Edwards lunged at him with a 30cm serrated hunting knife, that had been hidden in his jacket.

It went through Soper's forearm to such depths that it came out the other side.

Soper's father, NewstalkZB political editor Barry Soper, was present for the sentencing at Wellington District Court today.

During sentencing Judge Peter Hobbs repeatedly stressed that he was legally bound to take into account the eight months served in jail on remand, and four months on electronically monitored bail, while Edwards was waiting to be sentenced.

"I have read the victim impact statement, and it is clear that the victim continues to suffer physically from your actions.

"It is not yet certain whether he will fully recover. It is possible that he will continue to suffer some disability from your actions."

Judge Hobbs noted Henry Soper had also suffered had financial and emotional impacts, which he said were not surprising.

"There was an element of premeditation on your behalf.

"You took with you into a city precinct a 30cm hunting knife. You waited for the victim outside.

"The use of a hunting knife is serious, it is potentially a lethal weapon. It is also worth noting that at the time you were on a community work sentence."

Judge Hobbs admitted the sentence for four months of home detention would not appear to be enough, if looked at in isolation.

"A deterrent sentence is required, people cannot carry knives in public and use them to inflict injuries such as this.

"However you have already effectively served a 16 month sentence of imprisonment, on remand following your arrest.

"Had you not already spent 16 months effectively in prison, plus four months home detention, I would be sentencing you to prison. But because you have successfully completed that I will sentence you to four months home detention."

Edwards was sentenced to four months of home detention on 24 hour curfew.

He will also pay reparations of $3000, and serve 200 hours of community work.